(1) Field of the Invention
The present invention relates to a connector for connecting electric wires or the like, which maintain waterproof characteristic between the connector and the electric wire.
(2) Description of the Related Art
Various electronic instruments are mounted on a motor vehicle as a mobile unit. The motor vehicle is equipped with a wiring harness for transmitting electric power and control signals to the electronic instruments. The wiring harness includes a plurality of electric wires and connectors. The electric wire is a so-called coated electric wire including an electrically conductive core wire and an electrically insulating coating which coats the core wire.
For example, a connector disclosed in Japanese Patent Application Laid-Open No. 2000-294336 is used as the connector described above. The connector disclosed in Japanese Patent Application Laid-Open No. 2000-294336 includes a connector housing and sealing member. The connector housing includes a tube-shaped outer housing and a plurality of plate-shaped housings. The plate-shaped housing is provided with a terminal receiving groove for receiving a terminal fitting to which an electric wire is attached.
The sealing member includes a plurality of sheet-shaped sealing pieces made of resilient material such as rubber. The sheet-shaped sealing piece is attached to the plate-shaped housing so as to maintain a waterproof characteristic between the sheet-shaped sealing piece and the electric wire attached to the terminal fitting received in the terminal receiving groove of the plate-shaped housing.
The connector described above is assembled as follows: The terminal fitting with an electric wire is received in the terminal receiving groove of the plate-shaped housing and the sheet-shaped sealing piece is attached to the plate-shaped housing. Then, the plate-shaped housings are laminated with each other and thus laminated plate-shaped housings are received in the outer housing. Thus, the connector having a structure as described above is assembled and is coupled with a mating connector. In the connector thus assembled, the sheet-shaped sealing piece maintains waterproof characteristic between the sheet-shaped sealing piece and the electric wire so as to prevent liquid such as water from entering into the terminal receiving groove by way of the electric wire.
A connector disclosed in Japanese Patent Application Laid-Open No. 2004-349072 uses a sealing material such as urethane foam instead of using the sheet-shaped sealing piece disclosed in Japanese Patent Application Laid-Open No. 2000-294336. When the connector is assembled, the terminal fitting with an electric wire is received in the terminal receiving groove of the plate-shaped housing, the plate-shaped housings are laminated with each other, and the laminated plate-shaped housings are received in the outer housing and thereafter, a sealing material filling tank provided in the outer housing is filled with the sealing material.
As for the connector disclosed in Japanese Patent Application Laid-Open No. 2000-294336, when the plate-shaped housings are assembled with each other, the sheet-shaped sealing pieces made of rubber or the like abut against each other. Therefore, the plate-shaped housings must be assembled with each other resisting against resilient restoring force of the sheet-shaped sealing piece. Further, as for the connector disclosed in Japanese Patent Application Laid-Open No. 2000-294336, the plate-shaped housing is not provided with any means for fixing the sheet-shaped sealing piece. Therefore, when the plate-shaped housings are assembled with each other, the sheet-shaped sealing piece might possibly come off from the plate-shaped housing due to the restoring force of the sheet-shaped sealing piece. Therefore, as for the connector disclosed in Japanese Patent Application Laid-Open No. 2000-294336, it is difficult to assemble the plate-shaped housings without coming-off of the sheet-shaped sealing piece, resulting in that the connector is difficult to be assembled.
As for the connector disclosed in Japanese Patent Application Laid-Open No. 2004-349072, its assembly characteristic is good, however, if the sealing material subjected to the filling-up is once hardened, the maintenance cannot be performed since the sealing material cannot be separated from the outer housing. Further, since there are many controlling items for the sealing material, therefore there is a problem that the control of the sealing material is not easy.